S1 Measure Selection

  • The RMET was selected for this study due to its status as the most widely used test for the assessment of mentalizing, as evidenced by the 8,185 citations on Google Scholar.
  • The Frith-Happé Animations was chosen due to its status as one of the most prevalent mentalizing assessment tools in the context of Autism Spectrum Disorder (989 citations on Google Scholar). Additionally, it exhibits robust psychometric properties, particularly in terms of known-group validity (Livingston et al., 2021; White et al., 2011).
  • The Hinting Task and the Faux-pas Test are two widely used instruments, and both satisfy the two criteria established by Quesque et al. (2024) for a test to be deemed capable of assessing mentalizing. In this classification, ideal tests of mentalizing should be able to distinguish between mentalising and lower-level processes and, secondly, require the representation of mental states and the ability to distinguish between one’s own and others’ mental states (mentalising criterion; nonmerging criterion).
  • Both Hinting Task and the Faux-pas Test met these criteria, but neither the RMET nor the Frith-Happé animations met the criteria for mentalising and nonmerging as defined by this classification.

S2 Exploratory hypotheses

  1. We hypothesize that each test will uniquely explain a statistically significant proportion of the variance in each self-report of mentalizing. We also hypothesize that the Hinting Task and the Faux-pas Test will demonstrate a higher incremental validity compared to the RMET and the Frith-Happé Animations (Quesque & Rossetti, 2020).

  2. Because the mentalizing tests and self-report measures inherently entail measurement errors, we will compute a latent variable from the combined measures and examine the incremental validity of combined performance. This will test the idea that using multiple tests provides a more comprehensive assessment of mentalizing abilities, reinforcing the importance of multimethod approaches in both research and clinical neuropsychological evaluations.

  3. Last, based on previous results suggesting that self-report mentalizing measures may capture the perceived performance (rather than the actual performance) at mentalizing tasks, we will explore the incremental validity of both performance and perceived performance at mentalizing tasks against self-reported mentalizing measures. We hypothesize that the performance at mentalizing tests predicts variance in self-report measures beyond that explained by perceived performance.

  4. Finally, we hypothesize that performance at mentalizing tests, when combined into a latent variable, will explain unique variance in self-report measures of psychosocial functioning (loneliness and broad psychosocial functioning), beyond the variance explained by performance at reasoning and language tests. Furthermore, we explore the contribution of three distinct latent variables —mentalizing tests, perceived performance, and self-reports— on psychosocial functioning outcomes, while controlling for performance in reasoning and language tasks. We hypothesize that perceived performance and self-reports of mentalizing will explain unique variance in psychosocial functioning.


S3 Monte Carlo simulations

library(MASS)

IRI_REAS = .05
IRI_LANG = .05

MZtest_IRI_1 = .25 
MZtest_IRI_2 = .15 

REAS_LANG_1 = .40
REAS_LANG_2 = .30

MZtest_REAS_1 = .20 
MZtest_LANG_1 = .30
MZtest_REAS_2 = .10 
MZtest_LANG_2 = .20


simulate_analysis <- function(MZtest_REAS, MZtest_LANG, MZtest_IRI, REAS_LANG, IRI_REAS, IRI_LANG, n_participant = 320, n_simulations = 10000) {
  
  correlation_matrix <- matrix(NA, nrow = 4, ncol = 4)
  rownames(correlation_matrix) <- c("MZtest", "REAS", "LANG", "IRI")
  colnames(correlation_matrix) <- c("MZtest", "REAS", "LANG", "IRI")
  diag(correlation_matrix) <- 1.0
  
  correlation_matrix["MZtest", "REAS"] <- MZtest_REAS
  correlation_matrix["REAS", "MZtest"] <- MZtest_REAS  
  correlation_matrix["MZtest", "LANG"] <- MZtest_LANG
  correlation_matrix["LANG", "MZtest"] <- MZtest_LANG  
  correlation_matrix["MZtest", "IRI"] <- MZtest_IRI
  correlation_matrix["IRI", "MZtest"] <- MZtest_IRI 
  correlation_matrix["REAS", "LANG"] <- REAS_LANG
  correlation_matrix["LANG", "REAS"] <- REAS_LANG  
  correlation_matrix["REAS", "IRI"] <- IRI_REAS
  correlation_matrix["IRI", "REAS"] <- IRI_REAS  
  correlation_matrix["IRI", "LANG"] <- IRI_LANG
  correlation_matrix["LANG", "IRI"] <- IRI_LANG  
  mu = c(0, 0, 0, 0)

  inc_val_tot = p_value_total = rep(NA, n_simulations)

  for (i in 1:n_simulations) {
    dat_1 <- as.data.frame(MASS::mvrnorm(n=n_participant, mu=mu, Sigma=correlation_matrix))
    colnames(dat_1) <- c("Mentalizing", "REAS", "LANG", "IRI")
    dat_1$ID = 1:nrow(dat_1)
    
    res_crude = lm(IRI ~ REAS + LANG, data = dat_1)
    res_ToM = lm(IRI ~ REAS + LANG + Mentalizing, data = dat_1)
    
    INC_crude = summary(res_crude)$r.squared
    INC_ToM = summary(res_ToM)$r.squared
    
    p_value_total[i] = as.numeric(anova(res_crude, res_ToM)[2, "Pr(>F)"])
    inc_val_tot[i] = INC_ToM - INC_crude
  }

  return(data.frame(
    power = sum(p_value_total < 0.05)/n_simulations * 100,
    incremental_validity = mean(inc_val_tot)))
}

result_1_best_scenario <- simulate_analysis(MZtest_REAS_1, MZtest_LANG_1, MZtest_IRI_1, REAS_LANG_1, IRI_REAS, IRI_LANG)
result_2_worst_scenario <- simulate_analysis(MZtest_REAS_2, MZtest_LANG_2, MZtest_IRI_2, REAS_LANG_2, IRI_REAS, IRI_LANG)


print(result_1_best_scenario)
##   power incremental_validity
## 1 99.38           0.06181584
print(result_2_worst_scenario)
##   power incremental_validity
## 1 71.78           0.02282091

S4 References for the Monte Carlo simulation

Klein, H., Springfield ,Cassi R., & and Pinkham, A. E. (2024). Measuring social cognition within the university: The Social Cognition Psychometric Evaluation (SCOPE) battery in an undergraduate sample. Applied Neuropsychology: Adult, 31(5), 866–873. https://doi.org/10.1080/23279095.2022.2082875

Mansueto, G., Schruers, K., Cosci, F., van Os, J., Alizadeh, B. Z., Bartels-Velthuis, A. A., van Beveren, N. J., Bruggeman, R., Cahn, W., de Haan, L., Delespaul, P., Meijer, C. J., Myin-Germeys, I., Kahn, R. S., Schirmbeck, F., Simons, C. J. P., van Haren, N. E. M., & van Winkel, R. (2019). Childhood adversities and psychotic symptoms: The potential mediating or moderating role of neurocognition and social cognition. Schizophrenia Research, 206, 183–193. https://doi.org/10.1016/j.schres.2018.11.028

Meinhardt-Injac, B., Daum, M. M., & Meinhardt, G. (2020). Theory of mind development from adolescence to adulthood: Testing the two-component model. British Journal of Developmental Psychology, 38(2), 289–303. https://doi.org/10.1111/bjdp.12320

Müller, S., Wendt, L. P., & Zimmermann, J. (2023). Development and Validation of the Certainty About Mental States Questionnaire (CAMSQ): A Self-Report Measure of Mentalizing Oneself and Others. Assessment, 30(3), 651–674. https://doi.org/10.1177/10731911211061280

Murphy, B. A., & Lilienfeld, S. O. (2019). Are self-report cognitive empathy ratings valid proxies for cognitive empathy ability? Negligible meta-analytic relations with behavioral task performance. Psychological Assessment, 31(8), 1062–1072. https://doi.org/10.1037/pas0000732

Sty in the Mind’s Eye: A Meta-Analytic Investigation of the Nomological Network and Internal Consistency of the “Reading the Mind in the Eyes” Test—Anne Frieda Doris Kittel, Sally Olderbak, Oliver Wilhelm, 2022. (n.d.). Retrieved 8 April 2025, from https://journals.sagepub.com/doi/10.1177/1073191121996469

Wechsler, D. (2012). Wechsler Adult Intelligence Scale—Fourth Edition. https://doi.org/10.1037/t15169-000

Wendt, L. P., Zimmermann, J., Spitzer, C., & Müller, S. (2024). Mindreading measures misread? A multimethod investigation into the validity of self-report and task-based approaches. Psychological Assessment, 36(5), 365–378. https://doi.org/10.1037/pas0001310

Yeung, E. K. L., Apperly, I. A., & Devine, R. T. (2024). Measures of individual differences in adult theory of mind: A systematic review. Neuroscience & Biobehavioral Reviews, 157, 105481. https://doi.org/10.1016/j.neubiorev.2023.105481


S5 Mentalizing tests

Hinting Task

Examples

Story 1

George arrives at Angela’s office after a long, hot trip on the motorway. Angela immediately begins to talk about some business ideas. George interrupts Angela to say:

“Ugh, it has been a long, hot trip on the motorway.”

• 1st question: What does George really want to say when he says this?

• 2nd hint: George continues to say, “I am thirsty.”


Story 2

Marissa is going to the bathroom to have a shower. Anna just had a bath. When Marissa realises that the bathroom is dirty, she calls Anna and says:

“Couldn’t you find the cleaner, Anna?”

• 1st question: What does Marissa really want to say when she says this?

• 2nd hint: Marissa continues to say, “Sometimes you’re very lazy, Anna.”


Story 3

Jacob is going to the supermarket with his mother. They arrive at the sweets section and Jacob says:

“Look, those sweets look very good.”

• 1st question: What does Jacob really want to say when he says this?

• 2nd hint: Jacob continues to say, “I’m hungry, mum.”


Scoring

Hinting Item Scoring:
- 2 = Correct answer with first hint
- 1 = Correct answer with second hint
- 0 = Paraphrase of what character said or No response
=> 20 = Total possible points

Notes on scoring:
- If the respondent gives a 1-point response on the first hint, you may score a 1 and move on to the next question.
- If the respondent gives a 0-point response on the first hint, present the second hint.
- No further question is asked after the second hint.
- You may re-read a story once if the respondent requests it.


RMET

Scoring

RMET Item Scoring:
- 1 = Correct answer
- 0 = Incorrect answer
=> 36 = Total possible points


Frith-Happé Animations

Scoring

MCQ-categorization

Which of these 3 categories best fits the film clip you have just seen?

  1. No interaction

  2. Physical interaction

  3. Mental interaction

MCQ-feelings (correct answers in bold)

Coaxing:

  1. How do you think the Little Triangle feels at the end of the clip?

    • Proud
    • No feelings
    • Secure
    • Annoyed
    • Unsure
  2. How do you think the Big Triangle feels at the end of the clip?

    • Frustrated
    • Loving
    • Tense
    • Frivolous
    • No feelings

Mocking:

  1. How do you think the Little Triangle feels at the end of the clip?

    • No feelings
    • Fulfilled
    • Anxious
    • Mischievous
    • Devious
  2. How do you think the Big Triangle feels at the end of the clip?

    • Aggravated
    • Puzzled
    • Lonely
    • Satisfied
    • No feelings

Seducing:

  1. How do you think the Little Triangle feels at the end of the clip?

    • Lost
    • Cunning
    • Scared
    • Composed
    • No feelings
  2. How do you think the Big Triangle feels at the end of the clip?

    • Excited
    • Eager
    • No feelings
    • Cheerful
    • Foolish

Surprising:

  1. How do you think the Little Triangle feels at the end of the clip?

    • Provoked
    • No feelings
    • Bored
    • Pleased
    • Lucky
  2. How do you think the Big Triangle feels at the end of the clip?

    • No feelings
    • Terrified
    • Delighted
    • Disappointed
    • Uneasy

Faux-pas Test, Short version

Examples

Story 8

https://osf.io/cnpka/

Jeanette bought her friend Anne a crystal bowl for a wedding gift. Anne had a big wedding and there were a lot of presents to keep track of. About a year later, Jeanette was over one night at Anne’s for dinner. Jeanette dropped a wine bottle by accident on the crystal bowl, and the bowl shattered.

“I’m really sorry, I’ve broken the bowl,” said Jeanette. “Don’t worry,” said Anne, “I never liked it anyway. Someone gave it to me for my wedding.”

• 1st question: Did someone say something they shouldn’t have said? (Tests for detection of faux pas.)

• 2nd question: Who said something they shouldn’t have said? (Tests for understanding of faux pas.)

• 3rd question: Why shouldn’t they have said it? (Requires understanding mental state of listener.)

• 4th question: Why did they say it? (Requires understanding mental state of speaker.)

• 5th question: Did Anne remember that Jeanette had given her the crystal bowl?

• 6th question: How do you think Jeanette felt?

• 7th question: What is Jeanette giving Anne for her wedding?

• 8th question: How was the bowl broken?

Questions 7 and 8 are control questions to assess the good understanding of the story. Questions 2 to 6 are only asked if the participant answers “yes” on the first question.


Scoring

Faux-pas Test Scoring:

  • Control stories :

    • 2 = Correct answer to the first question
    • 0 = Incorrect answer to the first question

=> 10 = Control stories possible points

  • Faux-pas stories :

    • 1 = Correct answer to the question (for each of the six questions)
    • 0 = Incorrect answer to the question (for each of the six questions)

=> 30 = Faux-pas stories possible points

=> 40 = Total possible points


S6 Mentalizing self-reports

Interpersonal Reactivity Index - Perspective-Taking

Items

  1. I sometimes find it difficult to see things from the “other guy’s” point of view.

  2. I try to look at everybody’s side of a disagreement before I make a decision.

  3. I sometimes try to understand my friends better by imagining how things look from their perspective.

  4. If I’m sure I’m right about something, I don’t waste much time listening to other people’s arguments.

  5. I believe that there are two sides to every question and try to look at them both.

  6. When I’m upset at someone, I usually try to “put myself in his shoes” for a while.

  7. Before criticizing somebody, I try to imagine how I would feel if I were in their place.

Scoring

IRI - PT Scoring:

  • 7-point scale :

      1. “does not describe me well”
      1. “describes me well”

=> 49 = Total possible points


Interpersonal Reactivity Index - Empathic Concern

Items

  1. I often have tender, concerned feelings for people less fortunate than me.

  2. Sometimes I don’t feel very sorry for other people when they are having problems.

  3. When I see someone being taken advantage of, I feel kind of protective towards them.

  4. Other people’s misfortunes do not usually disturb me a great deal.

  5. When I see someone being treated unfairly, I sometimes don’t feel very much pity for them.

  6. I am often quite touched by things that I see happen.

  7. I would describe myself as a pretty soft-hearted person.

Scoring

IRI - EC Scoring:

  • 7-point scale :

      1. “does not describe me well”
      1. “describes me well”

=> 49 = Total possible points


Certainty About Mental States Questionnaire

Items

  1. I know my innermost wishes and desires.

  2. I can tell whether another person is at peace with themselves.

  3. I know how other people will react to something.

  4. I understand why certain things make me happy.

  5. I know what I am trying to achieve with my behavior.

  6. I can tell when a person in a group is feeling awkward.

  7. I know why I am interested in certain things.

  8. I can tell when other people don’t give their honest opinions.

  9. I understand my feelings.

  10. I know when other people are hiding their thoughts.

  11. I know what my virtues are.

  12. I can tell when other people are just pretending to find something funny.

  13. I know why I have a strong opinion on a subject.

  14. When I’m in a bad mood, I know the reason why.

  15. I know if a person is trustworthy.

  16. I know the reasons for my behavior.

  17. I can tell when other people are taking advantage of someone.

  18. I can tell if another person is bored by what I am saying

  19. I know how a person feels when I look at their face.

  20. I know what the best decision is for me in a difficult life situation.

Scoring

  • 7-point scale :

      1. “Never”
      1. “Always”

Six-item Reflective Functioning Questionnaire

Items

  1. People’s thoughts are a mystery to me

  2. I don’t always know why I do what I do

  3. When I get angry I say things without really knowing why I am saying them

  4. If I feel insecure I can behave in ways that put others’ backs up

  5. Sometimes I do things without really knowing why

  6. Strong feelings often cloud my thinking

Scoring

  • 7-point scale :

      1. “Do not agree at all”
      1. “Agree completely”

Affective and Cognitive Measure of Empathy - Cognitive empathy scale

Items

  1. I have a hard time reading people’s emotions

  2. I can tell when someone is afraid

  3. It’s obvious when people are pretending to be happy

  4. I usually understand why people feel the way they do

  5. I have a hard time figuring out what someone else is feeling

  6. I can tell when people are about to lose their temper

  7. I can usually predict how someone will feel

  8. I can usually tell how people are feeling

  9. I am not good at understanding other people’s emotions

  10. I can usually guess what’s making someone angry

  11. People don’t have to tell me when they’re sad, I can see it in their faces

  12. I find it hard to tell when someone is sad

Scoring

  • 5-point scale :

      1. “Strongly disagree”
      1. “Strongly agree”

Four-Item Mentalizing Index

Items

  1. I find it easy to put myself in somebody else’s shoes

  2. I sometimes find it difficult to see things from other people’s point of view

  3. I sometimes try to understand my friends better by imagining how things look from their perspective

  4. I can usually understand another person’s viewpoint, even if it differs from my own

Scoring

  • 4-point scale :

      1. “Strongly disagree”
      1. “Strongly agree”

S7 Psychosocial functioning self-reports

UCLA-Loneliness Scale-3

Items

  1. First, how often do you feel that you lack companionship ?

  2. How often do you feel left out ?

  3. How often do you feel isolated from others?


Scoring

UCLA-LS-3 Scoring:

  • 3-point scale :

    1. “Hardly ever”
    2. “Some of the time”
    3. “Often”

=> 9 = Total possible points


Short Social Functioning Questionnaire

Items

  1. I complete my tasks at work and home satisfactorily.

  2. I find my tasks at work and at home very stressful.

  3. I have difficulties in getting and keeping close relationships.

  4. I feel lonely and isolated from other people.

  5. I enjoy my spare time.

Scoring

  • Response range from 0 to 3 and vary according to items

1-

- 0) "Most of the time"
- 1) "Quite often"
- 2) "Sometimes"
- 3) "Not at all"

2-

- 3) "Most of the time"
- 2) "Quite often"
- 1) "Sometimes"
- 0) "Not at all"

3-

- 3) "Severe difficulties"
- 2) "Some problems"
- 1) "Occasional problems"
- 0) "No problems at all"

4-

- 3) "Almost all the time"
- 2) "Much of the time"
- 1) "Not usually"
- 0) "Not at all"

5-

- 0) "Very much"
- 1) "Sometimes"
- 2) "Not often"
- 3) "Not at all"

S8 Data analysis plan

Primary analysis

[Incremental validity of each test, against IRI-PT]. A commonality analysis will assess incremental validity of each mentalizing test in explaining variance in IRI-PT scores while controlling for language and reasoning. Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value. This will provide the percentage of variance (R²) explained by each test.

Exploratory analyses

Exploratory analysis 1 [comparison of incremental validity between tests, against IRI-PT]. We will compare the incremental R² of each test by computing pairwise differences, and apply bootstrapping (10,000 resamples) to assess statistical significance. This will identify the tests that have the largest incremental validity in IRI-PT scores.

Exploratory analysis 2 [incremental validity of each test, against each mentalizing questionnaire]. A commonality analysis will assess incremental validity of each mentalizing test in explaining variance in each mentalizing self-report while controlling for language and reasoning.Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value.

Exploratory analysis 3 [comparison of incremental validity between tests, against each mentalizing questionnaire]. We will compare the incremental R² of each test on each self-report at a time by computing pairwise differences, and apply bootstrapping (10,000 resamples) to assess statistical significance. This will identify the tests that explain the largest variance in each questionnaire.

Exploratory analysis 4 [incremental validity of a combination of all tests, against each questionnaire]. A commonality analysis will assess incremental validity of a latent variable of all mentalizing tests in explaining variance of each self-report of mentalizing while controlling for language and reasoning. Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value. This could inform us on the importance of assessing mentalizing using more than one test when performing a clinical neuropsychological assessment but also on which self-reports better reflect mentalizing performance.

Exploratory analysis 5 [incremental validity of each test, against a combination of all mentalizing self-reports]. A commonality analysis will assess incremental validity of each mentalizing test in explaining variance in a latent variable of all self-reports of mentalizing while controlling for language and reasoning. Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value.

Exploratory analysis 6 [comparison of perceived performance and mentalizing tests performance in explaining unique variance in mentalizing self reports]. A commonality analysis will assess incremental validity of each mentalizing test in explaining variance in a latent variable of all self-reports of mentalizing while controlling for perceived performance, language and reasoning. Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value. This will facilitate the identification of the variance of self-reports explained by mentalizing task performance that has not already been explained by perceived performance.

Exploratory analysis 7 [incremental validity of a combination of all tests, against each measure of psychosocial functioning (loneliness and broad psychosocial functioning)]. A commonality analysis will assess incremental validity of a latent variable of all mentalizing tests in explaining variance in each measure of psychosocial functioning while controlling for language and reasoning. Bootstrap estimation (10,000 simulations) will provide 95% confidence intervals, and nested linear models will provide insight into the p-value. This exploratory analysis will investigate whether a latent variable of all tests explains unique variance in psychosocial functioning measures.

Exploratory analysis 8 [incremental validity of tests, perceived performance, mentalizing questionnaire, against each measure of psychosocial functioning (loneliness and broad psychosocial functioning)]. This analysis extends the previous one by incorporating perceived performance on tests and scores from mentalizing questionnaires in explaining each measure of social functioning. This will allow us to isolate the variance in psychosocial functioning explained by three latent variables—mentalizing self-reports, perceived performance, and mentalizing tests—while controlling for the other factors, along with reasoning and language.

Commonality model

library(psych)
library(MASS)
library(yhat)
library(boot)

set.seed(12134)
r = runif(64, 0.1, 0.4)
mat = matrix(r, nrow=8)
diag(mat) <- 1 
mu=c(19, 17, 34, 16, 38, 6, 9, 11)
dat_1 <- as.data.frame(mvrnorm(n=19, mu=rep(0,8), Sigma=mat))
colnames(dat_1) <- c("RMET", "FauxPas", "Hinting", "Frith", "Iri", "UCLA3", "language", "reasoning")
dat_1$ID = 1:nrow(dat_1)

## Commonality analysis 
res_lm = lm(Iri~RMET+FauxPas+Frith+Hinting+language+reasoning, data=dat_1)
res_dom <- calc.yhat(res_lm)
boot.out = boot(data=dat_1, yhat::boot.yhat, 1000, 
                 lmOut=res_lm, regrout0=res_dom)
boot_results = booteval.yhat(res_dom, boot.out,bty="perc",.95,3)

Main analysis

Test of incremental validity

results_filtered <- boot_results$combCIaps["language,reasoning", 
                                          c("RMET.Inc", "FauxPas.Inc", "Frith.Inc", "Hinting.Inc")]

print(results_filtered)
##                              RMET.Inc        FauxPas.Inc          Frith.Inc
## language,reasoning 0.049(0.000,0.391) 0.266(0.003,0.639) 0.113(0.002,0.357)
##                           Hinting.Inc
## language,reasoning 0.121(0.000,0.501)

First secondary analysis

Comparison of incremental validity

results_filtered <- boot_results$combCIincDiff["language,reasoning", 
                                          c("RMET.Inc-FauxPas.Inc", "RMET.Inc-Frith.Inc", "RMET.Inc-Hinting.Inc", "FauxPas.Inc-Frith.Inc", "FauxPas.Inc-Hinting.Inc", "Frith.Inc-Hinting.Inc")]

print(results_filtered)
##                     RMET.Inc-FauxPas.Inc    RMET.Inc-Frith.Inc
## language,reasoning -0.217(-0.572,0.304)  -0.064(-0.315,0.312) 
##                     RMET.Inc-Hinting.Inc FauxPas.Inc-Frith.Inc
## language,reasoning -0.072(-0.341,0.212)   0.153(-0.128,0.473) 
##                    FauxPas.Inc-Hinting.Inc Frith.Inc-Hinting.Inc
## language,reasoning    0.145(-0.400,0.585)  -0.008(-0.381,0.281)

Plot

library(ggplot2)
## 
## Attaching package: 'ggplot2'
## The following objects are masked from 'package:psych':
## 
##     %+%, alpha
library(ggsignif)
## Warning: package 'ggsignif' was built under R version 4.1.3
data_plot <- data.frame(
  Test = c("RMET", "Hinting", "Frith", "FauxPas"),
  Incrementality = c(0.090, 0.082, 0.085, 0.101)
)

comparisons <- list(
  c("RMET", "Hinting"),
  c("RMET", "Frith"),
  c("Frith", "Hinting"),
  c("RMET", "FauxPas"),
  c("Frith", "FauxPas"),
  c("Hinting", "FauxPas")
)

annotations <- c("p = ns", "p = ns", "p = ns", "p = ns", "p = ns", "p = ns")

y_positions <- c(0.09, 
                 0.13, 
                 0.1,
                 0.19,
                 0.11,
                 0.16)

ggplot(data_plot, aes(x = Test, y = Incrementality, fill = Test)) +
  geom_bar(stat = "identity", color = "black", width = 0.2) +
  geom_signif(
    comparisons = comparisons,
    annotations = annotations,
    y_position = y_positions,
    tip_length = 0.03,
    textsize = 4
  ) +
  labs(
    title = "Incrementality of Predictors",
    x = "Predictors",
    y = "Incrementality (R² Difference)"
  ) +
  theme_minimal() +
  theme(
    plot.title = element_text(hjust = 0.5),
    legend.position = "none"
  ) +
  ylim(0, 0.2)

S9 Supplementary references

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